The present invention relates in general to circuits for pre-equalizing digital transmission lines and, in particular, to circuits utilizing fixed resistive pads and slope equalizers.
Constant Resistance filters are well known in the prior art, and are widely used to pre-equalize digital transmission lines. However, in order to accommodate different cable lengths, a family of slope equalizers has typically been used in the prior art. The electronic device used to pre-equalize the transmission lines was designed to accept a large family of plug-in equalizers.
The present invention overcomes this well known draw-back in the prior art with a single electronic circuit which can switch between various fixed resistive pads and slope equalizers.